Pressure device for lens grinding machines



NOV. 7, 1950 1 I GOLDBERG 2,528,952

PRESSURE DEVICE FOR LENS GRINDING MACHINES I Filed April 6, 1946 3 Sheets-Sheet 1 HIS ATTORNEYS H. GOLDBERG PRESSURE DEVICE FOR LENS GRINDING MACHINES Nov. 7, 1950 3 Sheets-Sheet 2 Filed April 6, 1946 INVENTOR HIS ATTORNEYS Nov. 7, 1950 GOLDBERG 2,528,952

PRESSURE DEVICE FOR LENS GRINDING MACHINES Filed April 6, 1946 3 Sheets-Sheet 5 I mm HIS ATTORNEYS Patented Nov. 7, 19 50 PRESSUREDE vronroa LENS GRINDING MACHINES V Henry Goldberg, Pittsburgh, Pa.

"Application, April6,,1946, SerialNo. 660,234

I 19 Claims.

. v 1 t I This invention pertains to a device for controlling and increasing the pressure application betWeen-a-tool and a piece'to be edge conditioned, V

and-particularly, to an' automatic pressure attachment for rimless edge grinding machines.

Previous to the present invention, difliculty has been encountered in providing a satisfactory edge grinding pressure attachment due to the sensitive; smooth, and continuously increasing nature of the'operation required. Commercial pressure attachments on rimless machines" at the present time are hand operated and-- theamount of pressurehas to be left to theoperators judgment and is more or less guess work. Some lenses receive more pressure thanneeded-and chipand crack;

* Figure 1' is a front perspective othersdo-not receiveencugh pressure and con sume moretime than needed. The operator has to move constantly from onemachine to another to shift thepressure -weight on each machine which is moved bylhand along the guide-rod to increase the pressure a little at a time, making it necessary for the-operator towalk up and down a battery of machines: at 'leas'tfour times before a particular lens is finished in onemachine. For example, the manin charge of a battery of ten machines utilizing'twent'y-five feet of floor space in starting at the first machine; can load ten in approximately fifteen minutes. He then returns to the first, l'ookshafter the lens increases the pressure and continues until he'reachesthe tenth machine, which takes approximately five minutes; Repeating this operation each time, fifteen minutes are spent in loading and ten to fifteen minutes are spent in increasing the pressure, making atotal of thirty-five minutes before the operator canremove the finished lens from the first machine. .Additionalitimewill be required. to progressively move the lenses fromlthe other machines. g I

Although automatic pressure devices have been devised, they havenot been commercially practical-for a: num-beu Off reasons and; as aresuit; the. art has continued: to. use manually operated. pressure controls.v

And, it. has been an object of my invention. to

I devise an automatic pressure attachment. that WillibS commerciallyfpracticail: and. foolproof in utilization;

Another object has been to provide a device improved automatic pressure device for surface conditioning machines.

A still further object has been to increase the efficiency of operation of a lens grinding machine and to minimize spoilage.

These and many other objects of my invention will appear from theembodiment chosen for the purpose of illustration.

In the drawings:

view in elevation of a rimless edgegrinding machine employing my invention.

Fig.2 is a side view in elevation of the machineof Fig. 1'. Y I

Fig. 3 is a top plan view of the machine of Fig. 1 with housing parts connections. 3 Fig. 4' is a side view in elevation of a device constructed in accordance with my invention, the dot and dash lines of A show it in an inoperative position; the" full lines'of- B'show itat a starting "7 position; and the dotted lines of C show it at the end of an operative: movement.

-Figure- 4;. showing a pressure control member at position '3' and" a circuit for indicating position C of-.Fig..4-.

Figs. 6; 7 and 8 are enlarged Side sectional views in elevation of a position-sensitive switch for opening and-closing circuit-connections to an actuating motor for-the device of Fig. 4. Fig. 6 corresponds to dot and dash line position A. Fig. 7" correspondstto full line position B, and Fig. 8 correspondsto dot'and dot line position C of Fig. 4-.

Fig; 9 is a somew hat diagrammatic circuitar-= rangement-showing a connected relationship for a. position-sensitive switch. and an actuating motor of- Fig. 4.

Fig. 10 is an enlarged perspective detail view. in elevation of a pressure control member or ele.- ment: shown. in amounted relationship in Fig. 4.

Edge. grinding machines such as employed in the optical. art are generally belt driven and.pro-.

ing Wheel, as eifected by fluid motor l4, and as: limitedbya stop-'element'll on frame I!) and adjustable fingers I 3 on framev I2. In such a removed to show driving vided with either a transversely reciprocating machine, it is customary to provide a pattern piece former, or template I! that corresponds to the desired'shape or contour of a finished lens and is adapted to abut against a contact plate l8 to pattern the grinding action on the lens IS. A micrometer adjustment I9 is shown in Figure 1 for adjusting relationship of the guide plate to the template l1. It is also customary in the art to provide transversely adjustable chuck means 20 and 2| for positioning the template I! and a lens I6 to be ground and gear means for rotating the template and lens while held by such chuck means. The chuck means 202l is mounted in a pivoted head portion of the machine in order that the lens can be moved toand from or into and r 4 such as a light 13 and warn the operator that the operation has been completed.

A suitable circuit, actuating connection, or energizing system for actuating motor 56 is shown in Figure 9 and includes a source of power 58 that is connected through terminals c' and d of a mercury switch 51. Asshown particularly in. Figures 6, 7 and 8, the switch 51 has a suitable electric-current conductinggfluid such .as mercury e enclosed within a non-conducting cup or container portion 1 thereof that will automatical- 11y turn the switchon and off by connecting and out of an operative position with respect to the grinding wheel. 7

The device of my present invention may be adapted to any conventional type of edge grinding machine and is connected by lever means to the pivoted lens piece. :carrying head or operating member in such a manner that an application of grinding pressure may be effected by moving the lens towards the grinding wheel with an increasing force as the edge-conditioning operation progressesw Referring particularly to Figures 1, '4 and 5, I have shown an automatic pressure translating or applying device which comprises a carrier arm, member, or bracket 50 having asupport i constructed and arranged to be pivoted at 52 to an;

extension of the frame Ill. Thecarrier member" 5!! is provided with a pair of longitudinally spaced apart, laterally extending portions 54a and, 54b

at oppositeends thereof which rotatably journal a: shaft 55. through the portion 54b and is shown :ccnnected The shaft 55.: atone end: extends to :an electric motor1'56. .'It will be apparent that i the' shaftor weight supporting rack me'rribert5irv which is provided with indentations for adjust? ably moving or advancing thewe'ight therealong may be an extension of the shaft of .the motor-56.

A major portion of'the shaft 55 that is located between the projections 54aand 54b 'is"pr0vided w'ith'threads 'af as shown, to receive an adjusting member or weight portion 60, seeparticularly Figure 10. lhe weight portion is shown provided with a slot orinme 6| extending; therethrough which is ovalfor "oblong" in shape; Itwill-be noted that its upper 'surfaces'BZ "are threaded to engage the threaded portion a' of the shaft -A connector or leverarm 53 extends downwardly as a part ofthefcarrierlifl and is'connected'by a rod 54 to an extension of the pivoted head 23 of the grindingmachine. The weight of the parts of the 'carrier member are so located with respect to tl"1e pivot point 52 that they are in substantial balance at the beginning of the edge grindingopierationQasshown by full line' position .B i of Figure 4. 'Thus, when'thev device is moved.to an-inoperative position A, as indicated by dot and dash lines in Figure 4,

it will stay-there until'raised to the full line position .B.* The dot and .dotiine of position;v C shows the device at the, end of itspressure strokeor when a maximunji pressure application is being elfected. 1 r? Referring to igures parent that when -,the device is moved to the position B,1 current .willflow between points c and d through theliquid conductor e, see Figure 7, to'actuatemotor56 and-rotate the extending support member orishaft 55 and its threaded portion a: to'pro'gressi-vely advance the weight limgfigures. The extending support member or shaft 7 55. Ahandle or hook fi3iex tends from a top'face I of the member Gil; in this manner, the surfaces 1520f the member 6!! can be raised to clear the threaded portion a of the shaft 55 and to permit therweight member to be moved to anyposition along such shaft. Thisisfadvantageous 'inmoving the weight back to its original starting posi-' tion after the completion of an edge-grinding operation or for starting the atany de' sired position along a.

Atits extendingend, the shaft 5 5 isprovided V with a non-threaded portion 1) ofslightly less.

diameter than the threaded portion a. Its length or extent corresponds -to'a length dimension'of the ,weight member '60 taken alongthe axis of the slot or hole ELtherethrough. As shown in Figures 2 and 4, at the completion of a grinding or; edging operation, the weight 60 slides'off the threads a onto the non-threaded portion'b, and,

in 'so'doing, may move a spring-like switch element' 10 into contact witha switch pole -'H', see

Figures 2 and 5, which closes an electric circuit through a source of power 12 to lightan indicator portion or member 60' towards the left of the 55 serves as a rack or support which may, as shown, mesh with the weightportion or member 60 to advance the. latter progressively therealong. This movement gradually raises the right hand 'zportion of the carrier 50 and thus gradually applies the full weight of the member fill tof'move lens IS with increasing," pressure against or towards the grinding wheel.- That is,:as the weight 60 moves to the left of the figures, or in other words, towards thezportion bflof the "shaft 55, the'center of gravity of' the arm 5|] shifts to the left and gradually increases-the effective pressure with which the lens is urged against the grinding wheel. At the finish of'an 'edgegrinding operation, the. operator lifts the weight member 60 back to its starting position on a.

Although the edge grinding machine, itself,

is not a part of my invention, I will briefly describe atypical machine as shown particularly in Figures 1, 2211(1-3. A suitable motive agency 25 drives belt wheel 26 that is feathered on shaft 21; and, the'latter' drives grinding wheel 46 and belt wheel 28that is'featheredon its opposite end Belt wheel 28'drives wheel 29 and shaft 30 to actuate'worm 3| which meshes with worm 6,77 anus, it will bea geanflt Gear 32; actuates, verticalshaft: 33s. and: helicaLgear 34': The helicalgear 34:meshes2withr.

helical: gear: 35 feathered; on. clutch: shazft 36" that actuates lens supporting: shafts; 43a: and43b in unison, through clutch. halves; 3,8, shaft 39, spur gears. 40a, 40b, Ha, 4"lb,'42"a,.and..4 2b that are:

mounted on the pivoted. or movable head 23-.

Thezshaftx43b and its associated: chuck 2.1- may" be-moved into and out off'positiom by meansy lfl andx45.. g

aThe lens carryingthead 2 3.: is;pivotally mounted on shaft 39, by a pair of arms [2a and I2?) extend- I irigs upwardly: from' the reciprocating carrying frame [2,. see Figure 1?, The-movable head 23 may.- be locked. in an up. position by engaging: lower latch. endof pivoted arm 24 with pin l on.

theextensionsupport. arm |-2b of; frame I2. .Thedriving; connections. forthee lens [6 can. be disconnected. by pullinghand wheel 31' outwardly to; disconnect clutch halves 3.8, see Figure 3;

The threads-a; on the shaft 5550f: the. pressure That: is, this switch can also be utilized to. automatically turn cff'ordisconnect the motor 55' at'the end of'a certain period of time or at the end of-the movements of: the weight" 69. For example, if the operator wishes to let' themotor 55 run when the weight 60' isat position C, a small additional. amount of conductor fluid 8 may be added to the container fin order that switch contact at will be closed. instead of open as shown in Figure 8. That; is, mercury may'be added or removed to; effectthe desired operative timing.

'By utilizing. my invention, the efliciency of a lens' grinding battery of machines can be increased and a smooth,.continuously increasing pressure applicationcan beobtained. spoilage has been decreased to a remarkable extent, substantially. to a. vanishing point, There is no guess work or sudden increaseof pressure. For example, the weight 6.11 can move down the threaded'rodiat a rate ofsapproximately one inch' per minute assuring a very slow and uniform pressure increase. It will: also be noted that the driving connections for the screw shaft: 55-

are independentof those pertaining to theedge, ing-machine, itself; this is an important feature of my present invention taken in connection with the fact that the motor 56 is carried by the pivoted: weight-carryingbracket orarm member That'is, my'device may be mounted on any suitablemachine, can beused manually if? the motor 56.0r its power supply fails, and spoilage orchipping of the lens is nil. The uneven, jarring action incident to the operation of a pressure apparatusgeared to a, grinding. machine has been eliminated;v The weight t0, due to, the extent of its threads 62:, gradually and smoothly moves off the threaded portion a of shaft upon portion by the diameter of portion 1) preferably substantially; corresponds to the diameter; of. portion. a; 75.

Ma a shaft rotatablypositioned' in one of said extending portions androtatably mounted in and extending through the other of? said extending" portions, a weight member: adiustably carried by:

amass-a between; depressed; portions;- or: valleys of": its; threads. Aswill be appreciated, thepitch ofthe-n threads (1 and 62. will, with the; speed. of": motor- 61b; govern the timing of: the operation; as previeously' indicated; I prefer to utilize a relatively:

slow. speed motor. For example ,the-timingmay besuch that the weight or-balance member 60. moves: from, its startingposition B-to its final. position. C in approximatelyt minutes. Izhave been able; to speed up a battery of" machinesby;

employing the present'invention and over a test'e 7 ing: period of approximately seven weeks have n-otahadone chipped or spoiled lens.

It'will' be apparent" to those skilledin the art,- that: various changes, alterations and additions to the. device of my invention may be madewithout-departing from the spirit and, scope thereof as indicated by. the appended claims;

WhatI claimis; i; A pressure increasing device adapted to be operably connected to; an operating member for;

moving a piece relative to; a tool in an edging machine, comprising a carrier member; a pivot support. for said carrier member, means onsaid carrier member constructedand arranged to operab'lyconnect it to the, operating" member'of' the machine, .a shaftoperably carried by said carrier.- member, means on said carrier; member for; actuating said. shaft, a weight; member operably positioned on said: shaft and constructed:

and arranged to move therealong: when said shaft: is' actuated, and. control means on. Said carrier member for connecting and disconnecting: said actuating means, said control means:v

haying portionssensitive to the pivoted position ofisaidc r-rier-member. I

' '2'."A:pressure increasing device adapted to be:

operably connected: to: an operating'member for moving; a; piece:.relative to a tool in an edging machine, a carrier member having a pairof laterally extending'portions at opposite longitu dinal ends thereof; apivot support; for said; car-- rier-member, means for connecting said carrier member tothe operating member of the machine,

said shaft, a motor mounted on said carriermem- Weber adjacent said last-mentioned extending portion thereof, said motor being operably connected to said shaft for rotating it; a power supply forsaid motor, a mercury switch sensitive to the pivoted position of. said carrier member and con his, necting said motor to said power supply.

3. A. pressure increasing device adapted to be operably connected to an operating member for moving a piece relative; to. a tool in. an edging machine, comprising a carrier member having means for'operably connecting saidcarrier mem her to the operating member of the machine, a shaft rotatably positioned in saidv projecting portions. and extending through: one of them, a motor operably connected. to, the extending end of: said' shaft; a weight member; operably positioned on; said shaft and constructed and arranged to move along said shaft to change the pivoted position of saidcarriermember when said shaft is rotated, an indicator circuit,. a switch,

in. said indicator circuit constructed and arranged to be closedv when said; weight: member has reachedone end of said carrier member;

transversely: extendingportionsatopposite ends: thereof, a pivot support for said carrier member, 1

4; A. pressure: increasing; device. adapted: to, be:

7 operably connected to an operating member for moving 'a piece relative to a tool in an edging machine, comprising a carrier member, a pivot support for said carrier member located beyond its normal center of gravity, means for operablyconnecting said carrier member to the operating member of the machine, a shaft rotatably mounted on said carrier, actuating means on said carrier'connected to said shaft, said shaft having one portion threaded therealong and terminating in an unthreaded portion, a Weight member having a slot therein to receive said shaft, said weight member having threads along at least a portion of said slot constructed andv being constructed and arranged to be closed when said weight member has moved thereon.

5. A pressure increasing device adapted to be operably connected to an operating member for moving a piece relative to a tool in an edge grinding machine, comprising a carrier member, a

pivot mount for said carrier member, means constructed and arranged to operably connect said carrier member to the operating member of the machine, a motor on said carrier member having' an energizing system, a weight portion on said carrier and constructed and arranged to be 8.; arm-extending from said provided with a movement translating connection for operably connecting'said device to the operating member, a motor on the end of said' arm member that isnearest to said pivot connection, a shaft, said shaft'at one end thereof extending into. said motor and being mounted: adjacent its other end on'said arm member, a weight portion associated with said motor and constructed and arranged to be moved along said shaft by said motor, an actuating connection'to said motor, a switch in said. actuating connection,

said switch having a contact constructed and arranged to disconnect said motor from *said actuating connection when said weight portion has been moved by said motor to the end of said shaft which is mounted on said arm member. 10. A pressure increasing device adapted to' be' operably connected to an operating member for moving a piece relative to a tool in an edging machine comprising, an arm member, a pivot support for said arm member located intermediate the end portions of its length and closer to one end portion than the other end portion there-'' of, means for connecting said arm member to the operating member of the machine, a shaft" extending along said arm member and being rotatably positioned thereon, motive means on said arm member adjacent the end portion thereof that is nearest to said pivot support, said motive means being operablyconnected to said moved therealong by said motor, and control means operably connected to said energizing system and sensitive to the pivoted position of said 5- carrier member for automatically disconnecting saidimotor from its'energizing system.

6. A pressure-applying device for a lens grinding machine that has an'operating member. for moving a work piece relative to a grinding surface, said pressure device being constructed and arranged to be pivotly mounted on the machine, movement translating connections carried by said device for operably connecting said device tothe operating member, a rack member car ried by: said device, a weight member operably mounted on said rack member for advancing movement therealong, a motor operably associated with said rack member and said weight member for advancing said weight member along said rack member to change the pivoted position of said device, an actuating connection to said motor, a shut-ofi in said actuating connection, and a position-sensitive means carried by said shut-off to disconnect said motor from saidactuating connection when said device is in a predetermined pivoted position.

'7. A pressure applying device as defined in claim 6 wherein said motor is an electric motor shaftfan actuating connection to said motive means, a weight; portion operably positioned on said shaft and constructed and arranged to move therealong from" said last-mentioned end portion thereof towards the other end portion thereof when said shaft is. operated by said motive means, and means on said arm member concarried by'said pivotally mounted pr'essuredevice, said actuating connection is an electric circuit, and said shut-off is an electric switch sensitive to the position of said electric motor.

8. A pressure applying device as defined in claim 6 wherein said shut-01f is constructed and arranged to disconnect said motor when said pressure device is at its opposite extreme pivoted positions.

9. A pressure applying device for a grinding machine having-an operating member for moving a work piece relative to a grinding'surface comprising an arm member provided with a pivot connection offsetly positioned therealong for mounting said device on the machine, a lever structed and arranged to disconnect saidmotive means from said actuating connection when said weight portion has moved to a predetermined position along said shaft.

11. A pressure increasing device as defined in claim 10, wherein said shaft is provided with teeth along its length, said weight portion has 7 a slot therethrough and an upper wall of Said slot has teeth thereon constructed and arranged to operatively engage ;the teeth on said shaft and to move said weight portion therealong when said shaft is operated by said motive means'and:

said slot is of sufficient length such that its teeth may be raised out of engagement with the teeth 1 of said shaft for moving said weight portion back to a starting position.

12; A pressure applying device for a grinding machine having an operating member for moving a Work piece and a grinding surface in a relative relationship towards each other, said pressure device being constructed and arranged to. be pivotally mounted on the machine, move-.

ment translating connections for operably connecting said device to the opearting member, an actuating motor-carried by said device, an actuatin'g connection to said motor, said motor being constructed and arranged to progressively move saidpressure device toa selected pivoted position,

and means operably associated with said motor and having a portion sensitive to the pivoted position of said pressure device that is constructed and arranged to disconnect said motor 13. A pressure applying device for a grinding. machine having an operating member for movarm member and being ing a work piece and a grindingsurface in a relative relationship towards each other, said pressure device being constructed and arranged to be pivotally mounted on the machine, movement translating connections for operably connecting said device to the operating member, a motor carried by said device, an actuating connection to said motor, said motor being constructed and arranged to progressively move said pressure device to a selected pivoted position, and means operably associated with said motor having a portion sensitive to the pivoted position of said pressure device that is constructed and arranged to disconnect said actuating connection from said motor when said pressure device has reached the selected pivoted position, said means for disconnecting said actuating connection being carried by said motor.

14. A pressure applying device as defined in claim 13, wherein said motor is an electric motor, said actuating connection is an electric circuit, and said means for disconnecting said actuating connection is an electric switch.

15. A pressure applying device as defined in claim 14, wherein said electric switch is provided with an electric contact whose position is sensitive to the operative position of said device.

16. A pressure applying device as defined in claim 15, wherein said electric contact is an electrical conducting fluid.

17. In a pressure-applying device for a grinding machine that has an operating member for moving a work piece relative to a grinding surface, an arm member, a pivot support between opposite ends of said arm member for pivotly mounting said arm member on the machine, said pivot support being located closer to one end than the other end of said arm, movement translating connections adapted to operably connect said arm member to the operating member, a i

rack member carried by said arm member and extending in a spaced-apart relationship therealong, a weight member adjustably-operably positioned on said rack for movement therealong, a motor carried by said rack member and being operably associated with said rack member to move said rack member and said weight member with respect to each other to advance said weight member along said rack member from a position adjacent the above-mentioned one end of said arm member, an actuating connection to said motor constructed and arranged to energize said motor, means in said actuating connection sensitive to the relative position of said weight member along said rack member to de-energize said motor.

18. In a pressure-applying device for a grinding machine that has an operating member for moving a work piece and a grinding surface in a relative relationship towards each other with a gradually increasing pressure and then in a relative relationship away from each other, an arm member, a pivot support offsetly positioned along said arm member for mounting said device on the machine, movement translating connections for operably connecting said arm member adjacent said pivot support to the operating member, a rack member extending along saidarm member and carried thereby, a weight member constructed to be positioned in operative engagement on said rack for advancing movement in one direction therealong from a starting position to change the pivoted position of said arm member, said weight member being constructed and arranged to be lifted out of engagement with said rack member and moved in an opposite direction therealong to the starting position, a motor carried by said arm member on said rack member, said motor being operably associated with said rack member to advance said weight member from the starting position along said rack member when said weight member is in engagement therewith to progressively change the center of gravity of said arm member with respect to said pivot support, an actuating connection to said motor, means carried by said motor adapted to connect and disconnect said motor with respect to said actuating connection, said means being adapted to disconnect said motor from said actuating connection when said weight member has been moved a predetermined distance along said rack member in engagement therewith.

'19. A pressure-applying device for a lens grinding machine that has an operating member for moving a work piece relative to a grinding surface, a pivot support on said pressure device intermediate and spaced from its opposite ends for pivotly mounting said device on the machine, said pivot support being located closer to one end of said pressure device than the other end thereof, movement translating connections carried by said pivot support for operably connecting said device to the operating member, a rack member carried by said device, a weight means operably mounted on said rack member for advancing movement therealong, a motor operably associated with said rack member and said weight means for advancing said weight means along said rack member to change the pivoted position of said device, an actuating connection to said motor, and a position-sensitive shut-oflf means in said actuating connection to disconnect said motor from said actuating connection I when said device is in a predetermined pivoted position.

HENRY GOLDBERG. REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 927,949 Clark July 13, 1909 1,048,059 Foppiano Dec. 24,1912 1,109,405 Gianni Sept. 1, 1914 1,272,474 Long July 16, 1918 1,449,266 Clarke Mar. 20, 1923 1,763,201 Norman June 10, 1930 1,906,739 Carruthers May 2, 1933 2,144,205 Tandy Jan. 1'7, 1939 2,175,719 Long Oct. 10, 1939 2,233,312 I-Iarrold Feb. 25, 1941 

